Springboot集成websocket实现消息推送和在线用户统计

<dependency>
   <groupId>org.springframework.bootgroupId>
   <artifactId>spring-boot-starter-websocketartifactId>
dependency>
1
2
3
4

在启动类上添加一个bean

@SpringBootApplication
public class CommonCodeApplication {

    @Bean
    public ServerEndpointExporter serverEndpointExporter(){
        return new ServerEndpointExporter();
    }

    public static void main(String[] args) {
        SpringApplication.run(CommonCodeApplication.class, args);
    }
}
1
2
3
4
5
6
7
8
9
10
11
12

核心代码

@Component
@ServerEndpoint("/websocket2/{username}")
@Slf4j
public class WebSocketDemo2 {

    private static Map<String, WebSocketDemo2> webSocketMap = new HashMap<>();

    private static Integer onlineUserCount = 0;

    private Session session;

    private String username;

    /**
     * 建立连接
     * @param username
     * @param session
     */
    @OnOpen
    public void onOpen(@PathParam("username") String username, Session session){
        this.username = username;
        this.session = session;
        webSocketMap.put(username, this);
        int count = addOnlineUser();
        log.info("当前在线用户：{}", count);
    }

    /**
     * 关闭连接
     * @param username
     */
    @OnClose
    public void onClose(@PathParam("username") String username){
        webSocketMap.remove(username);
        int count = reduceOnlineUser();
        log.info("当前在线用户：{}", count);
    }

    @OnMessage
    public void onMessage(String message) throws IOException {
        JSONObject jsonObject = JSONUtil.parseObj(message);
        String target = jsonObject.getStr("target");
        String msg = jsonObject.getStr("msg");
        if (target.equals("all")){
            sendMessageAll(msg);
        }
    }

    /**
     * 给特定的人发消息，用于业务中调用
     * @param usernames
     * @param message
     * @throws IOException
     */
    public void sendMessageSpecial(List<String> usernames, String message) throws IOException {
        for (String username : webSocketMap.keySet()) {
            for (String target : usernames) {
                if (username.equals(target)){
                    webSocketMap.get(username).session.getBasicRemote().sendText(message);
                }
            }
        }
    }

    /**
     * 给所有人发消息
     * @param message
     * @throws IOException
     */
    public void sendMessageAll(String message) throws IOException {
        for (WebSocketDemo2 item : webSocketMap.values()) {
            System.out.println("消息发送");
            item.session.getBasicRemote().sendText(message);
        }
    }



    public void sendMessage(String message) throws IOException {
        session.getBasicRemote().sendText(message);
    }

    /**
     * 用户离线
     * @return
     */
    public int reduceOnlineUser(){
       return  -- onlineUserCount;
    }

    /**
     * 累加在线用户
     * @return
     */
    public int addOnlineUser(){
        return ++ onlineUserCount;
    }

}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99

实现消息推送只要在业务代码中调用sendMessageSpecial()方法即可。

@RestController
@RequestMapping("/websocket")
public class WebSocketController {

    @Autowired
    private WebSocketDemo2 webSocketDemo2;

    @GetMapping("/t1")
    public String test1() throws IOException {

        System.out.println("这是业务代码...");
        
        String message = "消息被督办了！";
        List<String> usernames = new ArrayList<>();
        usernames.add("张三");
        usernames.add("李四");
        usernames.add("王五");
        webSocketDemo2.sendMessageSpecial(usernames, message);
        
        return "ok";
    }

}
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

四.测试

这里不用写前端去测试，大家可以使用这个网站进行测试
websocket测试
这里开了三个窗口进行测试，三个人的姓名分别是：张三、李四、王五

然后调用刚才的业务接口测试：http://localhost:8080/websocket/t1
调用成功后可以看到三个窗口中都收到了消息